The arc in my Philips MHN-TD ESS 70W/730

I love how the exhaust tip is horizontal to the pinch seals. This allow the arc to be uniform in the arctube, allowing more uniform temperature in the arctube and increasing lamp performance at horizontal burning.
This design of a tip horizontally to the pinch seals, exists also in the Philips HPI-T and the probe-start Osram HQI-T /N/SI lamps, but not with most American probe-start MH lamps.